Publications by authors named "Lyndon W Jones"

83 Publications

Effect of a Novel Omega-3 and Omega-6 Fatty Acid Supplement on Dry Eye Disease: A 3-month Randomized Controlled Trial.

Optom Vis Sci 2022 Jan;99(1):67-75

Nature's Way Canada, Dartmouth, Nova Scotia, Canada.

Significance: Supplementing diet with a novel combination of omega-3 and omega-6 fatty acids significantly improved symptoms in extremely symptomatic participants with dry eye disease (DED).

Purpose: This study aimed to determine the effect of daily intake of a novel combination of essential fatty acids on signs and symptoms of DED.

Methods: Participants with moderate to severe DED were enrolled in a prospective, randomized, double-masked parallel group study. Participants ingested either the treatment supplement containing omega-3 and omega-6 fatty acids (1200 mg eicosapentaenoic acid, 300 mg docosahexaenoic acid, 150 mg γ-linoleic acid) or the placebo (coconut and olive oil) daily for 3 months. To determine compliance, Omega-3 Index blood tests were conducted. At baseline and at 1 and 3 months, the following assessments were conducted: Ocular Surface Disease Index (OSDI) questionnaire and Symptom Assessment Questionnaire in Dry Eye, noninvasive tear breakup time, tear meniscus height, tear osmolarity, ocular redness, surface staining, Schirmer test, and meibography.

Results: Fifty participants (mean ± standard deviation baseline OSDI score, 52.2 ± 16.5) completed the study: 24 randomized to treatment and 26 randomized to placebo. Although there was an improvement in OSDI score at 3 months for both groups (treatment: -13.4 points, P = .003; placebo: -7.8 points, P = .02), participants with baseline OSDI scores >52 demonstrated an even larger significant improvement in symptoms with the treatment at 3 months compared with baseline (n = 13, -20.8 points, P = .002). There were no significant changes in any of the ocular assessments at 1 or 3 months (all P > .05). After 3 months, Omega-3 Index increased by 34% in the treatment group (baseline, 5.3 ± 0.8; 3 months, 8.0 ± 2.1; P < .001) and did not change in the placebo group (baseline, 4.8 ± 0.8; 3 months, 4.8 ± 0.6; P = .95).

Conclusions: Supplementation with eicosapentaenoic acid, docosahexaenoic acid, and γ-linoleic acid resulted in a significant and clinically meaningful improvement of dry eye symptoms in extremely symptomatic participants with DED (OSDI ≥52).
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http://dx.doi.org/10.1097/OPX.0000000000001826DOI Listing
January 2022

Global optometrist research ranking derived from a science-wide author database of standardised citation indicators.

Clin Exp Optom 2022 Jan 23;105(1):20-25. Epub 2021 Nov 23.

Centre for Ocular Research & Education, School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada.

Clinical Relevance: Publications in refereed scientific journals provide a rigorous research base that underpins clinical optometric practice. Leading optometrists who generate this literature can be identified and ranked using standardised citation indicators.

Background: This work seeks to identify and rank all optometrists included in a Science-Wide author database of standardised citation indicators (S-W) and to compare this ranking with the Global Optometrist Top 200 Research Ranking (T200).

Methods: A search was conducted for the names of all optometrists in the T200 who were included in the S-W, which is a world-wide listing of the top 2% of scientists in each of 174 subfield disciplines, ranked according to a composite citation indicator () that excludes self-citations and corrects for multiple authorships and author order.

Results: The names of 66 optometrists are found in the S-W. Of these, 58 are designated as working in the primary sub-field 'Ophthalmology & Optometry'; this listing, in rank-order of , is referred to as the 'S-W-derived Optometrist Research Ranking' (S-WORR). Australian optometrist Nathan Efron is ranked #1 in the S-WORR. The number (%) of optometrists in the S-WORR from each country is: the United States - 26 (45%), Australia - 12 (21%), the United Kingdom - 11 (19%), Canada - 5 (9%), Spain - 2 (3%), Hong Kong - 1 (2%) and South Africa - 1 (2%). The universities housing the equal highest number of optometrists in the S-WORR (five each) are the University of California, Berkeley, USA; the University of New South Wales, Australia; and Queensland University of Technology, Australia. There is a moderately strong correlation between T200 and S-WORR rankings (ρ = 0.6017, N = 58, p < 0.0001).

Conclusions: The S-WORR represents an elite cohort of optometrists who ought to be celebrated for their outstanding, leading and impactful contributions to optometric research.
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http://dx.doi.org/10.1080/08164622.2021.1981744DOI Listing
January 2022

Bibliometric analysis of the literature relating to silicone hydrogel and daily disposable contact lenses.

J Optom 2022 Jan-Mar;15(1):44-52. Epub 2021 Oct 3.

School of Optometry, The University of Alabama at Birmingham, Birmingham, Alabama, United States.

Purpose: Publication metrics are derived for the fields of silicone hydrogel (SH) and daily disposable (DD) contact lenses.

Methods: A search of the Scopus database for papers in the fields of SH and DD contact lenses found 979 SH and 291 DD papers. Subject-specific h-indices for SH lenses (h-index) and DD lenses (h-index) were derived, in relation to five categories - authors, institutions, countries and journals - to serve as measures of impact. A short list of the most impactful entities was generated for each of the above five categories in the SH and DD fields.

Results: A paper entitled "Soft contact lens polymers: An evolution" by Nicholson and Vogt was the most highly cited article (495 citations) in both SH and DD fields. The most impactful entities for the SH and DD fields were: authors - Lyndon Jones (h = 33) and Philip Morgan (h = 15); institutions - the University of Waterloo (h = 37) and the University of New South Wales (h = 15); countries - the United States (h = 45) and the United Kingdom (h = 24); and journals - Optometry and Vision Science (h = 33) and Contact Lens and Anterior Eye (h = 17). Overall, the SH field (h = 64) is far more impactful than the DD field (h = 34).

Conclusions: Impactful papers, authors, institutions, countries and journals in the SH and DD fields are identified. Optometry is revealed as the leading profession in relation to SH and DD publications.
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http://dx.doi.org/10.1016/j.optom.2021.05.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8712540PMC
December 2021

All soft contact lenses are not created equal.

Cont Lens Anterior Eye 2021 Sep 25:101515. Epub 2021 Sep 25.

Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada; Centre for Eye and Vision Research (CEVR), Hong Kong.

Soft contact lenses that have been prescribed by eye care practitioners are sometimes substituted for alternative lenses by unqualified, unregulated and sometimes even fully regulated lens suppliers, in the mistaken belief that there is essentially no difference between different soft lens types. This review considers the implications of inappropriately substituting soft contact lens types in terms of (a) lens properties: surface treatment, internal wetting agents, material, total diameter, back optic zone radius, thickness, edge profile, back surface design, optical design, power, colour (tint) and ultraviolet protection; and (b) lens usage: wearing modality (daily versus overnight wear) and replacement frequency. Potential aspects of patient dissatisfaction and adverse events when prescribed soft lenses are substituted for lenses with different properties or intended usage are considered. Substitution of 15 of the 16 lens properties considered (i.e. except for back surface design) was found to be related to at least one - and as many as six - potential sources of patient dissatisfaction and adverse ocular events. Contact lens are medical devices which are prescribed and fitted; they should never be substituted for another lens type in the absence of a new prescription further to a full finalised fitting, for the simple reason that all soft contact lenses are not created equal. A substituted lens may have properties that results in undesirable consequences in respect of vision, ocular health, comfort and cosmetic appearance, and may be incompatible with the lifestyle of the patient.
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http://dx.doi.org/10.1016/j.clae.2021.101515DOI Listing
September 2021

Bibliometric analysis of the keratoconus literature.

Clin Exp Optom 2021 Sep 21:1-6. Epub 2021 Sep 21.

School of Optometry, the University of Alabama at Birmingham, Birmingham, Alabama, USA.

Clinical Relevance: Clinicians, researchers funding agencies and indeed the general public can benefit from knowledge of the most highly cited papers and most impactful authors, institutions, countries and journals in the field of keratoconus.

Background: Bibliometrics relating to the keratoconus literature were derived to enable identification of the most impactful papers published, as well as the leading authors, institutions, countries and journals.

Methods: A search was undertaken of the titles of papers on the Scopus database to identify keratoconus-related articles. The 20 most highly cited papers were determined from the total list of 4,419 papers found. Rank-order lists by count were assembled for the 'top 20' in each of four categories: authors, institutions, countries and journals. A subject-specific keratoconus-related h-index (h-index) was derived for each constituent of each category to serve as a measure of impact in the field. The top 10 constituents of each category were ranked by h-index and tabulated for consideration.

Results: The h-index of the keratoconus field is 125. The 4,419 papers have been cited a total of 98,010 times, and 18.5% of these papers have never been cited. The most highly cited paper is a general review of keratoconus by Yaron Rabinowitz, who is also the most impactful author in the field (h = 31). The Cedars Sinai Medical Center in the United States produces the most impactful keratoconus-related papers (h = 36), and the United States is the most impactful country (h = 91). The is the most impactful journal (h = 55).

Conclusion: Keratoconus is a topic of high interest in the clinical and scientific literature. Highly cited papers and impactful authors, institutions, countries and journals are identified.
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http://dx.doi.org/10.1080/08164622.2021.1973866DOI Listing
September 2021

Topical Review: Bibliometric Analysis of the Emerging Field of Myopia Management.

Optom Vis Sci 2021 09;98(9):1039-1044

School of Optometry, University of Alabama at Birmingham, Birmingham, Alabama.

Significance: Identification of the most impactful articles, authors, institutions, countries, and journals in myopia management provides a useful baseline reference for clinicians, researchers, and funding agencies in respect of this emerging field.This work aims to assemble publication metrics for myopia management to identify the most impactful articles, authors, institutions, countries, and journals in this emerging field of research. A search of the titles of articles was undertaken on the Scopus database to identify myopia management-related articles. The 25 most highly cited articles were determined from the total list of 1064 articles found. Rank-order lists by count were assembled for the top 25 in each of four categories: authors, institutions, countries, and journals. A subject-specific myopia management-related h-index (hMM-index) was derived for the entire field, in addition to each of the four categories, to serve as measures of impact in the field. Top 15 lists were generated for each category ranked by hMM-index and tabulated for consideration. An article by Christine Wildsoet and colleagues, describing choroidal and scleral mechanisms of compensation for spectacle lenses in chicks, has generated the most citations (412); Earl Smith is the most impactful author (hMM = 19); the University of Houston produces the most impactful articles (hMM = 31); the United States is the most highly ranked country (hMM = 60); and Optometry and Vision Science is the most impactful journal. Although still in its infancy, myopia management is a topic of emerging interest in the clinical and scientific ophthalmic literature. Impactful authors, institutions, countries, and journals are identified. Optometry is revealed as the leading profession in relation to the publication of myopia management-related articles.
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http://dx.doi.org/10.1097/OPX.0000000000001766DOI Listing
September 2021

On the art and science of rigid contact lens fitting.

Clin Exp Optom 2021 08 7;104(6):684-690. Epub 2021 Jul 7.

School of Optometry, The University of Alabama at Birmingham, Birmingham, AL, USA.

Clinical Relevance: Examination of the literature can help answer the age-old question of the extent to which rigid contact lenses can be considered an art versus a science.

Background: This work aims to assemble rigid contact lens-related publication metrics to identify the most impactful papers, authors, institutions, countries and journals.

Methods: A search was undertaken of the Scopus database to identify rigid contact lens-related articles published since this lens type was first described in 1949. The 25 most highly cited papers were determined from the total list of 1,823 papers found. Rank-order lists by count were assembled for the 'top 25' in each of four categories: authors, institutions, countries and journals. A subject-specific rigid contact lens h-index (h-index) was derived for each author, institution, country and journal to serve as a measure of impact in the field. A short list of the top constituents in each category were ranked by h-index and tabulated.

Results: The most highly cited paper (467 citations) is entitled 'Risk factors and prognosis for corneal ectasia after LASIK', by Randleman et al. Karla Zadnik (h = 20; 32 papers) and Richard Hill (h = 10; 50 papers) are most impactful and prolific authors, respectively. The Ohio State University (h = 24; 96 papers) is the most impactful and prolific institution and the United States (h = 51; 680 papers) is the most impactful and prolific country. (h = 30; 233 papers) is the most impactful journal.

Conclusions: Impactful authors, institutions, countries and journals in the field of rigid lenses are identified. Although there is perhaps an artistic element to rigid contact lens fitting, the solid literature base underpinning the field of rigid contact lenses revealed here belies the notion that rigid lenses fitting is more of an art than a science.
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http://dx.doi.org/10.1080/08164622.2021.1945414DOI Listing
August 2021

Bibliometric analysis of the literature relating to scleral contact lenses.

Cont Lens Anterior Eye 2021 Aug 28;44(4):101447. Epub 2021 Apr 28.

School of Optometry, The University of Alabama at Birmingham, Birmingham, Alabama, USA.

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http://dx.doi.org/10.1016/j.clae.2021.101447DOI Listing
August 2021

The Impact of Incubation Conditions on In Vitro Phosphatidylcholine Deposition on Contact Lens Materials.

Optom Vis Sci 2021 04;98(4):341-349

Centre for Ocular Research & Education, School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada.

Significance: Previous in vitro measurements of contact lenses commonly investigate the impact of nonpolar tear film lipids (i.e., sterols). Polar lipids, however, are equally important stabilizing components of the tear film. This research explores and presents further knowledge about various aspects of polar lipid uptake that may impact contact lens performance.

Purpose: This study evaluated the impact of incubation time, lipid concentration, and replenishment of an artificial tear solution (ATS) on the uptake of phosphatidylcholine (PC) onto conventional hydrogel (CH) and silicone hydrogel (SH) contact lens materials.

Methods: Four SHs and two CH lens materials (n = 4) were soaked in a complex ATS containing radioactive 14C-PC as a probe molecule. Phosphatidylcholine uptake was monitored at various incubation time points (1, 3, 7, 14, and 28 days), with different ATS lipid concentrations (0.5×, 1×, 2×) and with and without regular replenishment of the ATS. Phosphatidylcholine was extracted from the lenses, processed, and counted by a β counter, and accumulated PC (μg/lens) was extrapolated from standard lipid calibration curves.

Results: All materials exhibited increasing PC deposition over time. Conventional hydrogel materials showed significantly lower PC uptake rates (P < .001) than any of the SH materials. Increasing lipid concentration in the ATS resulted in increased PC binding onto the contact lens materials (P < .001). Replenishing the ATS every other day, however, impacted the PC deposition differently, showing increased binding (P < .001) on CHs and reduced PC deposition for SH materials (P < .001).

Conclusions: Length of incubation, lipid concentration in the ATS, and renewal of the incubation solution all influenced the amount of PC that sorbed onto various lens materials and therefore need to be considered when conducting future in vitro deposition studies.
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http://dx.doi.org/10.1097/OPX.0000000000001680DOI Listing
April 2021

Bibliometric analysis of the meibomian gland literature.

Ocul Surf 2021 04 20;20:212-214. Epub 2021 Mar 20.

School of Optometry and Vision Science, Queensland University of Technology, Kelvin Grove, Queensland, Australia.

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http://dx.doi.org/10.1016/j.jtos.2021.03.004DOI Listing
April 2021

Global optometrist top 200 research ranking.

Clin Exp Optom 2021 May 4;104(4):471-485. Epub 2021 Mar 4.

School of Optometry, The University of Alabama at Birmingham, Birmingham, USA.

: Clinical optometric practice is underpinned by a rigorous research base, the primary evidence for which is publications in refereed scientific journals. Leading optometrists who publish this work should be identified and celebrated.: This work aims to derive publication metrics of the leading optometric researchers worldwide.: An extensive global search was conducted to discover leading optometric researchers; 480 names were identified. A custom-designed bibliographic search tool was developed to interrogate the Scopus database (Elsevier) and extract publication metrics using the unique Scopus Author Identifier number for each optometrist. On 13 January 2021, the full list was reduced to 200 optometrists (the 'Top 200') ranked by h-index - the 'Global Optometrist Top 200 Research Ranking'. The output from the custom tool automatically updates every 24 hours and is available at www.optomrankings.com.: The Top 200 have h-indices ranging from 20 to 67 and have published between 28 and 440 papers. Sixty one (30.5%) are women. Konrad Pesudovs has the highest h-index (67) and citations (51,193). The most prolific author is Robert Hess (442 papers). David Piñero is publishing at the fastest rate (17.6 papers per year). The Top 200 work in 13 nations, of whom 172 (86.0%) work in four nations: USA - 76 (38.0%), Australia - 43 (21.5%), UK - 41 (20.5%) and Canada - 16 (8.0%). Of the 72 institutions represented, the University of California, Berkeley, USA is home to the most Top 200 optometrists (17) and has the highest combined h-index of Top 200 optometrists (132).: The optometric profession is supported by a robust research base, prosecuted by a large international cohort of optometric researchers who publish extensively on a broad range of ophthalmic issues and whose work is highly cited. The 200 most impactful optometrists in the world are identified.
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http://dx.doi.org/10.1080/08164622.2021.1878863DOI Listing
May 2021

21st century citation analysis of the field of contact lenses.

Clin Exp Optom 2021 Jul 27;104(5):634-638. Epub 2021 Feb 27.

School of Optometry, The University of Alabama at Birmingham, Birmingham, USA.

: The scientific foundations for clinical contact lens practice are rooted in the ophthalmic literature. This analysis of contact lens papers celebrates contemporary research achievements in the contact lens field.: This work aims to assemble contact lens-related publication metrics so as to identify the most impactful papers published so far this century, as well the top countries, authors, institutions and journals.: A search was undertaken of the titles of papers on the Scopus database to identify contact lens-related articles published this century. The ten most highly cited papers were determined from the total list of 4,164 papers found. Rank-order lists by count were assembled for the 'top 25' in each of four categories: authors, institutions, countries and journals. A 20-year subject-specific contact lens h-index (h-20-index) was derived for each author, institution, country and journal to serve as a measure of impact in the field. The top 10 constituents (of the top 25) of each category were ranked by h-20-index and tabulated for consideration.: The most highly cited paper this century is entitled 'Soft contact lens polymers: An evolution', by Nicholson and Vogt. Lyndon Jones is the most impactful author, with a h-20-index of 32. The University of New South Wales (Australia) produces the most impactful contact lens-related papers, and the United States is the most highly-ranked country. is the most impactful journal in the contact lens field.: Contact lens materials and lens-associated keratitis are topics of high interest in the contemporary contact lens literature, with an emerging interest in orthokeratology for myopia control and glucose monitoring. Impactful 21 century authors, institutions, countries and journals are identified. Optometry is revealed as the leading profession in relation to the publication of impactful contact lens-related papers.
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http://dx.doi.org/10.1080/08164622.2021.1880867DOI Listing
July 2021

Bibliometric analysis of the refractive error field.

Clin Exp Optom 2021 Jul 24;104(5):641-643. Epub 2021 Feb 24.

School of Optometry, The University of Alabama at Birmingham, Birmingham, AL, USA.

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http://dx.doi.org/10.1080/08164622.2021.1880868DOI Listing
July 2021

21st century bibliometric analysis of the field of dry eye disease.

Clin Exp Optom 2021 Jul 23;104(5):639-640. Epub 2021 Feb 23.

School of Optometry and Vision Science, Queensland University of Technology, Kelvin Grove, Australia.

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http://dx.doi.org/10.1080/08164622.2021.1887581DOI Listing
July 2021

Bulbar Redness and Dry Eye Disease: Comparison of a Validated Subjective Grading Scale and an Objective Automated Method.

Optom Vis Sci 2021 02;98(2):113-120

Allergan plc, Irvine, California.

Significance: In this study, assessments of conjunctival redness were performed to evaluate whether patients with or without dry eye disease (DED) could be discriminated based on this measure. Our findings suggest that subjectively grading redness by quadrant, as opposed to automated en face measurements, may be more suitable for this purpose.

Purpose: This study aimed to quantify bulbar redness using the validated bulbar redness (VBR) grading scale and an automated objective method (Oculus Keratograph 5M; K5M) in participants with DED and non-DED controls.

Methods: Participants with DED (Ocular Surface Disease Index score ≥20 and Oxford scale corneal staining ≥2) and controls (Ocular Surface Disease Index score ≤10 and corneal staining ≤1) attended two study visits. In part 1A of visit 1, baseline bulbar redness was graded with the VBR scale in each conjunctival quadrant of both eyes, followed by automated measurements of temporal and nasal redness with the K5M. This was immediately followed by part 1B, during which a topical vasoconstrictor was instilled into both eyes. Redness assessments were repeated 5 and 30 minutes after instillation with both instruments. Participants returned 14 days later for visit 2, where the same assessments as for visit 1A were repeated.

Results: Seventy-four participants (50 DED and 24 controls) completed the study. There were statistically significant differences in redness between the DED and control groups when assessed with the VBR scale (14/16 comparisons; all, P < .05), whereas no significant differences in K5M-derived redness between the DED and non-DED groups were found at any location or time point. Both subjective and objective instruments detected statistically significant reductions in redness 5 and 30 minutes after instillation of the vasoconstrictor (all, P < .01).

Conclusions: Although both subjective and objective instruments were sensitive to detecting changes in redness induced by vasoconstriction, statistically significant differences in redness between DED and control groups were only found using the VBR scale.
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http://dx.doi.org/10.1097/OPX.0000000000001638DOI Listing
February 2021

Frequency of Contact Lens Complications Between Contact Lens Wearers Using Multipurpose Solutions Versus Hydrogen Peroxide in the United States and Canada.

Eye Contact Lens 2021 May;47(5):277-282

Indiana University (A.A.T.), School of Optometry, Bloomington, IN; University of Alabama at Birmingham School of Optometry (S.S.C., J.J.N.), Birmingham, AL; EyeCare Associates (D.G.), Hueytown, Alabama; Centre for Ocular Research and Education (CORE) (M.E., A.N., K.W., L.W.J.), School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada; and Centre for Eye and Vision Research (LWJ), Hong Kong.

Objectives: To retrospectively compare frequency of contact lens (CL) complications in soft CL users of hydrogen peroxide (H2O2) and multipurpose solutions (MPS).

Methods: This was a multicenter, retrospective chart review of CL records from each patient's three most recent eye examinations at academic and private practices. Patients must have used the same solution type for at least 3 years. Univariate analyses were conducted using t tests, and chi-square or Fisher's exact test for categorical measures.

Results: There were 1,137 patients included, with 670 (59%) using MPS and 467 (41%) H2O2. In total, 706 (62%) experienced at least one complication; 409 used MPS and 297 used H2O2. There was no difference in the proportion of patients experiencing at least one complication between MPS (61%) and H2O2 (64%) (P=0.38). Multipurpose solutions users were more likely to report discomfort compared with H2O2 users (P=0.04). Presumed microbial keratitis was experienced by 16 MPS and nine H2O2 users (P=0.60).

Conclusions: No significant differences were found in the frequency of CL complications between MPS and H2O2. H2O2 users were less likely to report discomfort and thus switching to a H2O2 system may be an alternative in CL users with discomfort.
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http://dx.doi.org/10.1097/ICL.0000000000000761DOI Listing
May 2021

Dry Eye Disease in University-based Clinics in Canada: A Retrospective Chart Review.

Optom Vis Sci 2020 11;97(11):944-953

Centre for Ocular Research and Education, School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada.

Significance: Dry eye disease (DED) imposes a substantial burden on patients, which can lead to significant economic consequences for society. We provide insights into the DED patient population and DED diagnostic/management practices in Canada, which to date have been inadequately addressed in the literature.

Purpose: The purpose of this study was to describe DED patient demographic/clinical characteristics alongside DED diagnosis/management in university-based optometry clinics in Canada.

Methods: This was a retrospective chart review of nonconcurrent non-Sjögren patients with DED at two university-based optometry clinics in Montreal and Waterloo. Waterloo charts with a diagnosis of DED and all charts from the Montreal dry eye clinic were considered for inclusion.

Results: Overall, 200 charts were reviewed. Most patients were female (Montreal, 76%; Waterloo, 72%), and the mean age was 57.2 ± 14.9 years at Montreal and 52.6 ± 20.1 years at Waterloo. Patients commonly reported multiple health conditions (e.g., allergies [Montreal, 44%; Waterloo, 36%]), and high use of systemic nonocular medications was observed (Montreal, 76%; Waterloo, 62%). Clinical signs and symptoms of DED were recorded more often in Montreal patients than in Waterloo patients (e.g., dryness symptoms, 100 vs. 72%; tear breakup time, 100 vs. 60%). Warm compresses (Montreal, 63%; Waterloo, 83%) and artificial tears (Montreal, 94%; Waterloo, 96%) were the most frequently recommended nonmedical treatment and ocular lubricant, respectively. Topical steroids were the most frequently prescribed medications (Montreal, 22%; Waterloo, 21%), with typically three to four different interventions recommended per patient at each clinic. No relationship was found between symptoms and clinical signs or recommended interventions.

Conclusions: This retrospective chart review provided the demographics, clinical characteristics, diagnosis, and management options for DED patients in Canadian university-based optometry clinics. The more comprehensive assessments conducted at Montreal may be beneficial to better monitor the progression of DED and to determine treatment effects over time.
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http://dx.doi.org/10.1097/OPX.0000000000001603DOI Listing
November 2020

The Effect of Antimicrobial Peptides on the Viability of Human Corneal Epithelial Cells.

Probiotics Antimicrob Proteins 2021 04;13(2):518-526

Centre for Ocular Research & Education (CORE), School of Optometry & Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada.

Antimicrobial peptides are polypeptides composed of less than 100 amino acids and are a class of antibiotics with strong activity against some infectious bacteria. This study examined the safety of four chosen antimicrobial peptides using primary human corneal epithelial cells (HCEC) and explored their potential therapeutic use. The efficacy of the peptides was also studied by evaluating the minimum inhibitory concentrations (MIC) against Gram-negative and Gram-positive bacteria. One of the peptides (polymyxin E) was found to have antibacterial efficacy against a common Gram-negative bacterium (MIC 1.56 μg/mL for Pseudomonas aeruginosa), and another one (nisin) was found to have antibacterial efficacy against a common Gram-positive bacterium (MIC 125 μg/mL for Staphylococcus aureus). Metabolic activity and live/dead/apoptotic effects were measured with fluorescent dyes after HCEC were exposed to the peptides for 30 min. Three of the peptides exhibited lower toxicity against HCEC than a currently marketed eye drop product. Regarding both efficacy and safety, two of the peptides (polymyxin E and nisin) were found to have potential use for treating ocular infections.
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http://dx.doi.org/10.1007/s12602-020-09692-1DOI Listing
April 2021

Effect of Artificial Tear Formulations on the Metabolic Activity of Human Corneal Epithelial Cells after Exposure to Desiccation.

J Vis Exp 2020 05 2(159). Epub 2020 May 2.

Centre for Ocular Research and Education (CORE), School of Optometry & Vision Science, University of Waterloo.

Artificial lipid-containing tear formulations are developed to reduce tear evaporation by the restoration of a deficient tear lipid layer. Artificial tear formulations that prevent cell desiccation will result in ocular surface protection and the maintenance of cell metabolic activity. During dehydration, cells undergo the process of loss of metabolic activity and subsequently cell death. This work describes a method for assessing the efficacy of artificial tear formulations. The metabolic dye (i.e., alamarBlue) changes from a low fluorescent molecule resazurin to a fluorescent molecule resorufin in viable cells. The biological performance of an artificial tear formulation is measured as the ability of the formulation to (a) maintain cell viability and (b) provide cell protection from desiccation. Growth media and saline are used as controls for the cell viability/desiccation tests. Cells are incubated with test solutions for 30 min and then desiccated for 0 or 5 min at 37 °C and 45% relative humidity. Cell metabolic activity after initial exposure and after cell desiccation is then determined. The results show the comparative effects of eye drop formulations on cell metabolic activity and desiccation protection. This method can be used to test dry eye formulations that are designed to treat individuals with evaporative dry eye.
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http://dx.doi.org/10.3791/60812DOI Listing
May 2020

The ocular surface, coronaviruses and COVID-19.

Clin Exp Optom 2020 07 13;103(4):418-424. Epub 2020 May 13.

Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada.

The ocular surface has been suggested as a site of infection with Coronavirus-2 (SARS-CoV-2) responsible for the coronavirus disease-19 (COVID-19). This review examines the evidence for this hypothesis, and its implications for clinical practice. Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), responsible for the COVID-19 pandemic, is transmitted by person-to-person contact, via airborne droplets, or through contact with contaminated surfaces. SARS-CoV-2 binds to angiotensin converting enzyme-2 (ACE2) to facilitate infection in humans. This review sets out to evaluate evidence for the ocular surface as a route of infection. A literature search in this area was conducted on 15 April 2020 using the Scopus database. In total, 287 results were returned and reviewed. There is preliminary evidence for ACE2 expression on corneal and conjunctival cells, but most of the other receptors to which coronaviruses bind appear to be found under epithelia of the ocular surface. Evidence from animal studies is limited, with a single study suggesting viral particles on the eye can travel to the lung, resulting in very mild infection. Coronavirus infection is rarely associated with conjunctivitis, with occasional cases reported in patients with confirmed COVID-19, along with isolated cases of conjunctivitis as a presenting sign. Coronaviruses have been rarely isolated from tears or conjunctival swabs. The evidence suggests coronaviruses are unlikely to bind to ocular surface cells to initiate infection. Additionally, hypotheses that the virus could travel from the nasopharynx or through the conjunctival capillaries to the ocular surface during infection are probably incorrect. Conjunctivitis and isolation of the virus from the ocular surface occur only rarely, and overwhelmingly in patients with confirmed COVID-19. Necessary precautions to prevent person-to-person transmission should be employed in clinical practice throughout the pandemic, and patients should be reminded to maintain good hygiene practices.
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http://dx.doi.org/10.1111/cxo.13088DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7272971PMC
July 2020

The efficacy of povidone-iodine, hydrogen peroxide and a chemical multipurpose contact lens care system against Pseudomonas aeruginosa on various lens case surfaces.

Cont Lens Anterior Eye 2021 Feb 27;44(1):18-23. Epub 2020 Feb 27.

Centre for Ocular Research and Education (CORE), School of Optometry & Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada. Electronic address:

Purpose: To determine the antimicrobial efficacy of a povidone-iodine system (PVP-I; cleadew, OPHTECS Corporation, Kobe, Japan), a peroxide system (AOSEPT Plus with HydraGlyde, Alcon, Fort Worth, TX), and a chemical multipurpose system (renu fresh, Bausch & Lomb, Rochester, NY) on contact lens case surfaces that are both in contact and not in contact with the solutions during lens disinfection.

Methods: The surfaces of the inner walls, underside of the lid, and lens holder (if applicable) of the cases were inoculated with P. aeruginosa ATCC 27853. The cases were disinfected with the solutions as per their manufacturer instructions. After disinfection, the inoculated surfaces were swabbed and the amount of surviving P. aeruginosa was determined. Following this experiment, separate cases were inoculated and disinfected as before. This time the cases were agitated after recommended disinfection time and the amount of P. aeruginosa in the disinfecting solution was quantified immediately, and again after resting for 7 days. Experiments were conducted in triplicate (n = 3).

Results: Units are expressed in log CFU. All three solutions significantly reduced P. aeruginosa on direct-contact surfaces (all p < 0.039). On non-contact surfaces, the reduction of P. aeruginosa in the PVP-I system (pre-disinfection: 6.8 ± 0.5, post-disinfection: 1.0 ± 0.0; p < 0.001) was significant, but not for the hydrogen peroxide system (pre-disinfection: 6.3 ± 0.6, post: 5.5 ± 0.5; p = 0.194) and the chemical multipurpose system (pre-disinfection: 6.6 ± 0.1, post-disinfection: 5.6 ± 0.8; p = 0.336). After 7 days post-disinfection, no P. aeruginosa regrowth was observed in the PVP-I system (Day 1: 1.0 ± 0.0, Day 7: 1.0 ± 0.0; p = 1) and the chemical multipurpose system (Day 1: 4.2 ± 0.2, Day 7: 1.8 ± 0.9; p = 0.012), however regrowth was observed in the hydrogen peroxide system (Day 1: 3.4 ± 0.6, Day 7: 6.1 ± 0.4; p = 0.003).

Conclusion: The PVP-I system was more effective against P. aeruginosa on non-contact surfaces than the hydrogen peroxide system or the chemical multipurpose system and is capable of inhibiting regrowth of P. aeruginosa for at least 7 days post-disinfection.
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http://dx.doi.org/10.1016/j.clae.2020.02.012DOI Listing
February 2021

Uptake and Release of Polyvinyl Alcohol from Hydrogel Daily Disposable Contact Lenses.

Optom Vis Sci 2019 03;96(3):180-186

Centre for Ocular Research and Education (formerly Centre for Contact Lens Research), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada

Significance: Polyvinyl alcohol is a wetting agent that could reduce the symptoms of dry eye and contact lens discomfort. Currently, only one lens type, nelfilcon A (DAILIES AquaComfort Plus), releases polyvinyl alcohol. The concept of releasing this agent from contact lenses could be applied to other lens materials.

Purpose: The purpose of this study was to measure the release of polyvinyl alcohol from commercially available hydrogel daily disposable contact lenses using refractive index and iodine-borate methods.

Methods: Etafilcon A, omafilcon A, and nelfilcon A were soaked in phosphate-buffered saline and 0.2% trifluoroacetic acid/acetonitile for 24 hours to remove residual blister pack components. The lenses were then incubated in a 10-mg/mL solution of polyvinyl alcohol for 24 hours. After the incubation period, the lenses were placed in 2 mL of phosphate-buffered saline. At specified time intervals, t = 0.5, 1, 2, 4, 8, 12, and 24 hours, the samples were evaluated using refractive index and an iodine-borate assay. Polyvinyl alcohol uptake was determined by extracting the lenses with methanol for 24 hours.

Results: There were no differences in the uptake of polyvinyl alcohol between lens types (P > .05). The release of this wetting agent for all lens types followed a burst-plateau profile after the first 30 minutes (P > .05). Nelfilcon A had a slightly higher release of polyvinyl alcohol (P < .05) than did etafilcon A but was similar to omafilcon A (P > .05).

Conclusions: The results suggest that the contact lenses tested in this study have similar efficiency in delivering polyvinyl alcohol.
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http://dx.doi.org/10.1097/OPX.0000000000001351DOI Listing
March 2019

A novel scale for describing corneal staining.

Clin Ophthalmol 2018 19;12:2369-2375. Epub 2018 Nov 19.

Centre for Ocular Research & Education, School of Optometry & Vision Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada,

The assessment of corneal staining is a commonly conducted procedure in both clinical practice and as part of various research studies. Different grading scales are employed by many clinicians and researchers to undertake this procedure for corneal staining comparisons between eyes, products and over time. This paper describes the development and use of a grading scale for corneal staining undertaken at an academic research site. The scale involves assessment of three factors across five corneal zones: type, area and depth. Staining type and area are graded on a 0-100 scale, and depth is graded on a 0-4 scale. These factors can be combined to create a three- or two-factor staining grade, or the factors may be reported individually. An additional benefit of this scale is that the staining scores may be reported by zone as "zone staining scores" or the scores of zones may be combined to provide an overall corneal "global staining score".
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http://dx.doi.org/10.2147/OPTH.S178113DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6251457PMC
November 2018

The Effect of Denatured Lysozyme on Human Corneal Epithelial Cells.

Invest Ophthalmol Vis Sci 2018 04;59(5):2006-2014

Centre for Ocular Research & Education, School of Optometry & Vision Science, Waterloo, Ontario, Canada.

Purpose: During contact lens wear, the amount of lysozyme deposited on contact lenses varies depending on the lens material. The binding of lysozyme to some contact lens materials may result in a conformational change that denatures the protein to an inactive form. This investigation evaluated the effect that denatured lysozyme has on human corneal epithelial cells (HCECs) by measuring cell viability and the release of inflammatory cytokines.

Methods: HCECs were exposed to lysozyme that was denatured to various activity levels. After 24-hour exposure to the lysozyme (1.9 mg/mL) in growth media, the cells were evaluated for cell viability using confocal microscopy. The metabolic activity of the cells was determined using an alamarBlue assay. Cell supernatants were analyzed for inflammatory cytokines.

Results: Using confocal microscopy, there was no detectable change in the viability of the HCECs after exposure to the denatured lysozyme. However, using alamarBlue, a decrease in the metabolic activity of the HCECs exposed to denatured lysozyme was detected. HCECs exposed to lysozyme that was 67%, 47%, and 22% active showed a reduction in metabolic activity when compared with native (100% active) lysozyme and the media controls (P < 0.05). Exposure to the denatured lysozyme also caused an increase in the release of inflammatory cytokines (P < 0.05) from the HCECs.

Conclusions: The results of this study show that denatured lysozyme can have a detrimental effect on HCECs. Both a reduction in metabolic activity and an increase in the release of inflammatory cytokines occurred after HCEC exposure to denatured lysozyme.
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http://dx.doi.org/10.1167/iovs.17-22260DOI Listing
April 2018

Cytotoxic and inflammatory effects of contact lens solutions on human corneal epithelial cells in vitro.

Cont Lens Anterior Eye 2018 06 14;41(3):282-289. Epub 2017 Dec 14.

Centre for Contact Lens Research, School of Optometry & Vision Science, University of Waterloo, 200 University Avenue West, Waterloo Ontario, N2L 3G1, Canada.

Purpose: To ascertain the effect that four contact lens (CL) multipurpose solutions (MPS) have on the viability and release of pro-inflammatory cytokines from human corneal epithelial cells (HCEC).

Methods: HCEC were exposed to four different MPS at various concentrations for 18 hours. The cells were also exposed to phosphate buffer, borate buffer, and PHMB. The cell viability was evaluated using the alamarBlue assay. The release of pro-inflammatory cytokines was measured using a Multiplex electrochemiluminescent assay.

Results: MPS-A, MPS-B and MPS-C all reduced cell metabolic activity p < 0.05 from control with MPS-A showing the greatest cytotoxic effect (maximum reduction, 90.6%). In contrast, MPS-D showed no significant reductions in cytotoxicity except at the highest concentration tested (19% reduction at 20% MPS concentration). Of the four cytokines evaluated MPS-C showed a substantial increase in the release of IL-1β, IL-6, IL-8, and TNF-α at higher concentrations when compared to control p < 0.05. At the 20% concentration of MPS-A and MPS-B the release of IL-1 β increased p < 0.05 but the release of IL-6, IL-8, and TNF-α decreased. MPS-D did not cause a change in the release of cytokines IL-1β, IL-6, IL-8 and TNF-α p > 0.05. Exposing the cells to borate buffer and PHMB caused an increase in the release of TNF-α p < 0.05.

Conclusions: This investigation demonstrates that at different concentration levels, several of the MPS tested showed a decrease in viability and an increase in the release of inflammatory cytokines from HCEC. The borate buffer component as well as PHMB appears to contribute to this pro-inflammatory reaction.
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http://dx.doi.org/10.1016/j.clae.2017.12.006DOI Listing
June 2018

In Vitro Effect of Lysozyme on Albumin Deposition to Hydrogel Contact Lens Materials.

Optom Vis Sci 2017 11;94(11):1047-1051

1Centre for Contact Lens Research (CCLR), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada 2Johnson and Johnson Vision Care, Inc., Jacksonville, Florida

Significance: Albumin deposition on contact lenses could be detrimental to contact lens (CL) wear because this may increase the risk of bacterial binding and reduce comfort. Lysozyme deposition on selected lens materials would reduce albumin deposition on lenses.

Purpose: This study aims to determine if lysozyme deposition on CLs could act as a barrier against subsequent albumin adsorption, using an in vitro model.

Methods: Six hydrogel CL materials (etafilcon A, polymacon, nelfilcon A, omafilcon A, ocufilcon B, and nesofilcon A) were evaluated. Four CLs of each type were soaked in lysozyme solution for 16 hours at 37°C. Lysozyme-coated lenses were then placed in vials with 1.5 mL of artificial tear solution containing I-labeled albumin for 16 hours at 37°C with shaking. Four uncoated lenses of each type were used as controls. Lenses soaked in radiolabeled albumin were rinsed in a phosphate-buffered saline solution, and radioactive counts were measured directly on lenses using a gamma counter. Albumin uptake on lenses was measured using a calibration curve by plotting radioactive counts versus protein concentration.

Results: Results are reported as mean ± SD. Lysozyme-coated etafilcon A lenses exhibited lower levels of deposited albumin than uncoated etafilcon A lenses (58 ± 12 vs. 84 ± 5 ng/lens; P < .05). There were no differences in albumin adsorption between control (uncoated) and lysozyme-coated polymacon (105 ± 10 vs. 110 ± 34 ng/lens), nelfilcon A (51 ± 7 vs. 42 ± 20 ng/lens), omafilcon A (90 ± 20 vs. 80 ± 38 ng/lens), ocufilcon B (87 ± 20 vs. 115 ± 50 ng/lens), and nesofilcon A (170 ± 29 vs. 161 ± 10 ng/lens) lens materials (P > .05). Uncoated nesofilcon A lenses deposited the highest amount of albumin when compared with other uncoated lenses (P < .05).

Conclusions: This study demonstrates that lysozyme deposited onto etafilcon A resists the deposition of albumin, which may potentially be beneficial to CL wearers.
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http://dx.doi.org/10.1097/OPX.0000000000001137DOI Listing
November 2017

Lipid Deposition on Contact Lenses when Using Contemporary Care Solutions.

Optom Vis Sci 2017 09;94(9):919-927

1Centre for Contact Lens Research, School of Optometry and Vision Science, University of Waterloo, Ontario, Canada 2Johnson and Johnson Vision Care, Inc., Jacksonville, Florida 3Eurolens Research, University of Manchester, Manchester, UK 4School of Optometry, University of Alabama, Birmingham, Alabama.

Significance: There remains only a small amount of data from human studies demonstrating the effect of contact lens/lens care solution combinations on the deposition of lipids. Therefore, information on the degree to which modern materials deposit lipids when used with contemporary care solutions would be valuable.

Purpose: The present study aims to determine the effect of lens care system combinations on levels of total lipid, cholesterol, and cholesteryl esters extracted from three different contact lenses (CLs) when used with four contemporary care systems.

Methods: Experienced CL wearers were recruited to participate in this study. Combinations of three CLs (etafilcon A [ETA], galyfilcon A [GALY], and senofilcon A [SENO]) and four CL care solutions (Biotrue, ClearCare, OPTI-FREE PureMoist, and RevitaLens Ocutec) were investigated. A total of 791 CLs were analyzed. Subjects were randomized to one lens type and then used all four lens care solutions in random sequence for 10-14 days before the CLs were collected and analyzed for the amount of cholesterol, cholesteryl esters, and total lipids.

Results: The mean range of cholesterol recovered across the different care solutions was 0.34-2.77 μg/lens, 3.48-4.29 μg/lens, and 4.75-6.20 μg/lens for ETA, SENO, and GALY lenses, respectively. Use of OPTI-FREE PureMoist with ETA lenses led to a significantly greater amount of cholesterol being recovered when compared to the use of the other solutions with ETA lenses (P < .05). The mean range of cholesteryl esters recovered across different care solutions was 1.31-2.02 μg/lens, 6.43-7.19 μg/lens, and 7.96-10.13 μg/lens for ETA, SENO, and GALY lenses, respectively. There were no differences in the amount of cholesteryl esters and total lipids extracted for a given lens type when used with any of the four care solutions (P > .05).

Conclusions: This study did not demonstrate conclusively that any of the solution/CL combinations were superior to any of the other combinations when the amounts of lipid deposition were compared among the tested lenses.
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http://dx.doi.org/10.1097/OPX.0000000000001114DOI Listing
September 2017

Effect of Time on Scleral Lens Settling and Change in Corneal Clearance.

Optom Vis Sci 2017 09;94(9):908-913

School of Optometry & Vision Science, Centre for Contact Lens Research, University of Waterloo, Waterloo, Ontario, Canada.

Significance: With the increase in the use of scleral contact lenses among practitioners, questions regarding lens settling are gradually gaining attention. This is because current studies support the notion that scleral lenses settle back over time. More research is needed to understand the exact cause and the factors that underpin such phenomenon.

Purpose: The present study aims to assess the effect of time on topographic corneal clearance of three scleral contact lenses of varying sagittal depths.

Methods: Three scleral contact lenses were fitted to 20 subjects with previous diagnosis of keratoconus (n = 18) or pellucid marginal degeneration (n = 2). The fit was based on corneal sagittal height measured with the Visante optical coherence tomographer (OCT) at 15 mm along the horizontal meridian. To select an appropriate lens from the diagnostic lens set, values of 325 μm (lens 1), 375 μm (lens 2), and 425 μm (lens 3) were randomly added in sequence to the corneal sagittal height. Subjects wore each lens for 1 hour. Corneal clearance was measured at 10-minute intervals for 1 hour using a custom ultra-long OCT. To assess change in clearance, central point and two mid-peripheral points (+3 mm and -3 mm) along an 8-mm chord were measured by taking differences at each time point up to 1 hour. Measurements were repeated for the two other lenses.

Results: Mean central corneal clearance loss for all three lenses was 33.83 ± 48.40 μm. This was 26 ± 27 μm (13 ± 14 μm, +3 mm; 34 ± 37 μm, -3 mm), lens 1; 35 ± 59 μm (38 ± 61 μm, +3 mm; 52 ± 69 μm, -3 mm), lens 2; and 41 ± 54 μm (33 ± 26 μm, +3 mm; 52 ± 48 μm, -3 mm), lens 3, respectively. There was no significant difference (P = 0.06) at central and other locations for lens 1 (location and over time). There were significant differences for both lenses 2 and 3 (P < .001, P = .01, respectively) for all three locations and over time.

Conclusions: There is a likelihood of clearance loss after 1 hour of lens wear. This varies between subjects, initial lens-fit relationship, and over time.
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http://dx.doi.org/10.1097/OPX.0000000000001111DOI Listing
September 2017

Impression Cytology of the Lid Wiper Area.

J Vis Exp 2016 08 9(114). Epub 2016 Aug 9.

Centre for Contact Lens Research, University of Waterloo.

Few reports on the cellular anatomy of the lid wiper (LW) area of the inner eyelid exist and only one report makes use of cytological methods. The optimization of a method of collecting, staining and imaging cells from the LW region using impression cytology (IC) is described in this study. Cells are collected from the inner surface of the upper eyelid of human subjects using hydrophilic polytetrafluoroethylene (PTFE) membranes, and stained with cytological dyes to reveal the presence of goblet cells, mucins, cell nuclei and various degrees of pre- and para-keratinization. Immunocytochemical dyes show cell esterase activity and compromised cell membranes by the use of a confocal scanning laser microscope. Up to 100 microscopic digital images are captured for each sample and stitched into a high-resolution, large scale image of the entire IC span. We demonstrate a higher sensitivity of IC than reported before, appropriate for identifying cellular morphologies and metabolic activity in the LW area. To our knowledge, this is the first time this selection of fluorescent dyes was used to image LW IC membranes. This protocol will be effective in future studies to reveal undocumented details of the LW area, such as assessing cellular particularities of contact lens wearers or patients with dry eye or lid wiper epitheliopathy.
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http://dx.doi.org/10.3791/54261DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5091770PMC
August 2016

Prolonged Ocular Retention of Mucoadhesive Nanoparticle Eye Drop Formulation Enables Treatment of Eye Diseases Using Significantly Reduced Dosage.

Mol Pharm 2016 09 8;13(9):2897-905. Epub 2016 Aug 8.

Department of Chemical Engineering, University of Waterloo , Waterloo, Canada.

Eye diseases, such as dry eye syndrome, are commonly treated with eye drop formulations. However, eye drop formulations require frequent dosing with high drug concentrations due to poor ocular surface retention, which leads to poor patient compliance and high risks of side effects. We developed a mucoadhesive nanoparticle eye drop delivery platform to prolong the ocular retention of topical drugs, thus enabling treatment of eye diseases using reduced dosage. Using fluorescent imaging on rabbit eyes, we showed ocular retention of the fluorescent dye delivered through these nanoparticles beyond 24 h while free dyes were mostly cleared from the ocular surface within 3 h after administration. Utilizing the prolonged retention of the nanoparticles, we demonstrated effective treatment of experimentally induced dry eye in mice by delivering cyclosporin A (CsA) bound to this delivery system. The once a week dosing of 0.005 to 0.01% CsA in NP eye drop formulation demonstrated both the elimination of the inflammation signs and the recovery of ocular surface goblet cells after a month. Thrice daily administration of RESTASIS on mice only showed elimination without recovering the ocular surface goblet cells. The mucoadhesive nanoparticle eye drop platform demonstrated prolonged ocular surface retention and effective treatment of dry eye conditions with up to 50- to 100-fold reduction in overall dosage of CsA compared to RESTASIS, which may significantly reduce side effects and, by extending the interdosing interval, improve patient compliance.
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http://dx.doi.org/10.1021/acs.molpharmaceut.6b00445DOI Listing
September 2016
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